What are Cofunction Identities?
A function f is cofunction of a function g if f(A) = g(B) when A and B are complementary angles.
sin(A) = cos(B), if A + B = 90°
sec(A) = scs(B), if A + B = 90°
tan(A) = cot(B), if A + B = 90°

Cofunctions
What is a cofunction. Finding the cofunction. Using the cofunction relationship

Cofunctions

Cofunction Identities
This video explains the cofunction identities and how to determine cofunctions given a function value. Most cofunction values are verified on a calculator.

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